Improved shoot fly resistant sources by gamma irradiation induced mutations in sorghum (Sorghum bicolor (L.) Moench)

Abstract

Shoot fly is one of the major pests of sorghum in India, which causes substantial economic losses in sorghum production. Levels of host plant resistance to sorghum shoot fly is low to moderate. Mutagenesis is a potential tool to induce new variation for crop improvement. Seeds of sorghum genotype IS 18551, a shoot fly resistant line, were mutated by irradiating with 500 Gy gamma rays. These mutants were evaluated under field condition for two seasons at four locations for resistance to shoot fly. Finally 30 mutant lines showed resistance to shoot fly across three hot spot locations over the resistance check (IS 18551) and three mutant lines showed break down of resistance and was on par with susceptible check (DJ 6514) were identified. Genetic analyses of these lines would throw light on the genes underlying resistance/susceptibility and facilitate development of genotypes with enhanced resistance.